An anisotropic numerical model for thermal hydraulic analyses: application to liquid metal flow in fuel assemblies

33rd UIT (Italian Union of Thermo-fluid dynamics) Heat Transfer Conference

物理学;力学

Vitillo, F.^1 ; Di Maio, D Vitale^1 ; Galati, C.^1 ; Caruso, G.^1

Sapienza University of Rome, Dep. of Astronautical Electrical and Energy Engineering (DIAEE), Corso Vittorio Emanuele II, 244, Rome

00186, Italy^1

关键词: Conjugated heat transfer;    Lead cooled fast reactor;    Non-linear eddy-viscosity model;    Nuclear engineering applications;    Reynolds stress tensors;    Shear-stress transport;    Thermal hydraulic behaviors;    Thermal-hydraulic analysis;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/655/1/012058/pdf
DOI  :  10.1088/1742-6596/655/1/012058

学科分类：力学，机械学

来源: IOP

【 摘 要 】

A CFD analysis has been carried out to study the thermal-hydraulic behavior of liquid metal coolant in a fuel assembly of triangular lattice. In order to obtain fast and accurate results, the isotropic two-equation RANS approach is often used in nuclear engineering applications. A different approach is provided by Non-Linear Eddy Viscosity Models (NLEVM), which try to take into account anisotropic effects by a nonlinear formulation of the Reynolds stress tensor. This approach is very promising, as it results in a very good numerical behavior and in a potentially better fluid flow description than classical isotropic models. An Anisotropic Shear Stress Transport (ASST) model, implemented into a commercial software, has been applied in previous studies, showing very trustful results for a large variety of flows and applications. In the paper, the ASST model has been used to perform an analysis of the fluid flow inside the fuel assembly of the ALFRED lead cooled fast reactor. Then, a comparison between the results of wall-resolved conjugated heat transfer computations and the results of a decoupled analysis using a suitable thermal wall-function previously implemented into the solver has been performed and presented.